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INDONESIA
EKSAKTA: Journal of Sciences and Data Analysis
Published by Universitas Islam Indonesia
ISSN : 27160459     EISSN : 27209326     DOI : 10.20885
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Earth & Planetary Sciences Materials Science & Nanotechnology
Ekstakta is an interdisciplinary journal with the scope of mathematics and natural sciences that is published by Fakultas MIPA Universitas Islam Indonesia. All submitted papers should describe original, innovatory research, and modelling research indicating their basic idea for potential applications. The Journal particularly welcomes submissions that focus on the progress in the field of mathematics, statistics, chemistry, physics, biology and pharmaceutical sciences.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 231 Documents
 1   2   3   4   5 
The Effect of CaO Weight from Snail Shell (Pilla Ampullacea) On Its Activity As Heterogeneous Catalyst on Biodiesel Conversion Of Bran Oil Hikmah Fatmawati; Wellyana Puspitasari; Rohini Pujiarti; Sesy Ardyanti; Is Fatimah
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 18, ISSUE 1, February 2018
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol18.iss1.art7

Abstract

Research on utilization of snail (Pilla ampullacea) shell as CaO source for biodiesel conversion from rice bran oil has been investigated. CaO was derived by calcining the shell at pada 900oC for 2 h. The powder obtained from the process was characterized using x-ray diffraction (XRD),  energy dispersive x-ray (EDX), Fourier-Transform Infra-red (FTIR) and surface basicity test. In order to test the activity of catalyst, effect of catalyst weight on the yield of conversion as studied. Results show that the derived material is composed from dominantly CaO and the material demonstrates activity in rice bran conversion into biodiesel. Compared to  NaOH, the CaO catalyst exhibits more effectively active as shown by the higher yield. From varied catalyst weight, it is obtained that at the range of 2.5-10% catalyst weight does not affect significantly to the increasing yield. 
Effect of Adding Aspergillus niger Mushroom on Patchouli Fermentation Process Alivia Maulidina Pawestri; Noor Fitri
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 19, ISSUE 1, February 2019
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol19.iss1.art2

Abstract

Indonesia is one of the biggest exporter country for essential oils in the world. One of Indonesia's essential oil export commodities is patchouli oil. Almost 90% of the world’s patchouli oil are exported from Indonesia. Various studies to improve the quality of Indonesian patchouli oil were carried out. In this research, the process of fermentation of patchouli raw material was conducted to enhance the quality of patchouli oil. Patchouli fermentation was carried out using A. niger. Preparation processes were carried out prior to distillation including withering, size reducing and fermenting. Patchouli was withered for 24 hours. Patchouli was cut into pieces and weighed as much as 800 grams (3 leaves: 1 stem) after withered. Patchouli fermentation was conducted anaerobically for 20 hours. Varying the addition of A. niger used was 5 mL, 10 mL, 15 mL and 25 mL mixed in 400 mL of distilled water. The amount of A. niger colonies was 8.8 x 105 /mL. Extraction of patchouli oil was performed by water bubble distillation. The chemical and physical properties of the patchouli oil were analyzed and compared to the quality standard of patchouli oil according to SNI 06-2385-2006. Chemical compound of patchouli oil was identified using GC-MS. The main compound of the patchouli oil is patchoulol. The GC-MS result indicates that patchoulol content increases with the increasing addition of A. niger. The content of patchoulol was detected up to 93.75 %w/w in patchouli oil. The optimal concentration of  A. niger is 1.875% that produces the highest patchoulol content with an increase of up to 194.6 % compared to those of without A. niger (J0).
Pengaruh Bahan Kalsium Oksida pada Waktu Pengikatan Pasta Beton Geopolimer dan Konvensional Mochammad Qomaruddin; Khotibul Umam; Istianah Istianah; Yayan Adi Saputro; Purwanto Purwanto
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 19, ISSUE 2, August 2019
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol19.iss2.art8

Abstract

Pasta geopolimer merupakan pasta dengan bahan limbah fly ash sebagai binder dan pasta konvensional merupakan pasta yang menggunakan semen sebagai bahan utama binder. Substitusi penambahan bahan limbah pada penelitian ini bertujuan untuk komparasi antara pasta geopolimer dan pasta konvensional dengan beberapa variasi limbah. Metode yang digunakan dalam penelitian ini adalah eksperimental setting time dengan prosentase variasi perbandingan binder  100% FA : 0%, 90% : 10%,  80% : 20. Aktivator 1 : 2 (NaOH dan Na2SiO3) Molaritas yang dipakai yaitu 8M dan 12M. Proses Setting time (waktu pengikatan awal) yaitu saat pencampuran binder dengan air maupun aktivator kemudian penurunan jarum terjadi setelah waktu terjadi setiap 5 menit. Dari hasil setting time dengan perbandingan pasta konvensional dan pasta geopolimer menunjukan bahwa waktu ikat awal paling cepat terjadi pada pasta geopolimer 12M penambahan gypsum 20% yaitu selama 7 menit. untuk waktu ikat awal paling cepat dengan perbandingan pasta geopolimer 8M dan 12M terjadi pada pasta geopolimer 12M. Sedangkan pada untuk pengikatan akhir terjadi paling cepat pada pasta geopolimer 12M dengan penambahan gypsum 8M yaitu selama 15 menit.
Study of Quartz Activation, Effect of pH and Ion Fe2+ Concentration in Supporting Processes K.D. Nugrahaningtyas; D.M. Widjonarko; I.Y. Indriasari
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 11, ISSUE 2, August 2010
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Iron oxide supported in quartz had been done. This research were studied activation in quartz, effect of pH and ion Fe2+ concentration to the iron oxide formation in quartz and quartz itself. Activation were done using variation of activator concentration and time contact. The variation of activator concentration were 1 and 4M, and variation of the time contact were 15, 30, 60, 90 and 1440 minutes (24 hours). Quartz in optimum condition of activation was used for the supporting processes. Processes were conducted in ion exchange method. Supporting processes were done using variation of pH and ion Fe2+ concentration. The variation of pH were 5, 7 and 9, and variation of ion Fe2+ concentration were 0, 0,001, 0,005 and 0,01M. The sampels were analyzed using gravimetric and X-Ray Diffraction methods. The result showed that the acidity of quartz increased after activation comparing with quartz before activation. It means the activation sites formed in quartz. The activation reached optimum condition in activator concentration 1M and the time contact was 30 minutes. The result showed that supporting processes affected by pH and ion Fe2+ concentration. Iron oxide supported in pH 7 and 9, and maximum supported in concentration of ion Fe2+ 0,005M.     Keywords: iron oxide, quartz, activation, supporting processes, pH, ion Fe2+ concentration
Synthesis, Characterization and Aplication of TiO2 Alumina Pillared Montmorillonite Photocatalyst Iwan Sumarlan, Is Fatimah, Karna Wijaya
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 13, ISSUE 1-2, August 2013
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol13.iss1-2.art3

Abstract

Dispersion of TiO2 on montmorillonite pillared aluminium has been done successfully. The photocatalyst were prepared by intercalation of Al13 onto natural montmorillonite and then calcined at 500oC. Titania dispersion onto aluminium pillared montmorillonite was carried out by impregnation method at the theoritic concentration of 0.4, 0.8, 1 and 3% titania. The photocatalyst then characterized by XRD, porosimetry, SEM and Diffuse Reflectance Visible methods. Results of characterization showed that the basal spacing and specific surface area as well as total pore volume were decreased after dispersion of TiO2 on PILM, meanwhile SEM image exhibited that beside in the pores of PILM, the TiO2 was also dispersed on the surface of PILM. DR UV characterization result indicated that the band gap of TiO2 dispersed PILM for Ti/PILM 0,8%, Ti/PILM 1% and Ti/PILM 3% was 3.66, 3.19 and 3.19 eV respectively. Photodegradation optimum of methyl orange was found to be at Ti/PILM 1%Keywords : montmorillonite, pillarization, photocatalyst, methyl orange, TiO2
Studi Komputasi Metode Ab Initio Dft Dalam Kajian Struktural Dan Sifat Elektronik Senyawa Kalsium Borohidrid-Diamonia Sebagai Penyimpan Hidrogen Muhammad Arsyik Kurniawan
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 15, ISSUE 1-2, 2015
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol15.iss1-2.art3

Abstract

Telah dilakukan kajian teoritis tentang struktur dan sifat elektronik dari senyawa Ca(BH4)2·2NH3 sebagai salah satu material yang berpotensi digunakan untuk menyimpan dan penghasil hidrogen melalui proses dehidrogenasi. Perhitungan teoritis energi, Density of States dan celah pita elektron dari struktur kompleks Ca(BH4)2·2NH3 dilakukan dengan Density Functional Theory (DFT) dan fungsi energi perubahan dan korelasi menggunakan metode Generalized Gradient Approximation (GGA). Berdasarkan analisis struktur dan sifat elektronik kristal kompleks Ca(BH4)2·2NH3 diperoleh atom–atom hidrogen yang berpotensi sebagai sumber molekul hidrogen yaitu hidrogen (Hδ-) dari BH4 dan hidrogen (Hδ+) dari NH3 dalam bentuk ikatan dihidrogen N– H···H–B. Hasil perhitungan simulasi didapatkan besar celah energi band gap sebesar 5,68 eV, yang menyatakan material ini sebagai insulator. Dari data analisis lebih lanjut terhadap studi pelepasan molekul H2 vs NH3 sebesar 2,30 eV vs 1,52 eV, mengindikasikan material Ca(BH4)2·2NH3 lebih rendah untuk melepaskan molekul H2 dibanding NH3, data ini sesuai dengan hasil pengamatan eksperimen.
Adsorption Isotherm of Cr(VI) Using Mg/Al Hydrotalcite with Molar Ratio 2:1 Bayu Wiyantoko; Puji Kurniawati; Tri Esti Purbaningtias
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 14, ISSUE 1, February 2014
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Hydrotalcite is a material which is used in various application and one of them as an adsorbent of Cr(VI). Hydrotalcite was synthesized using co-precipitation method with Al(NO­3)3.9H2O and Mg(NO3)2.6H2O as raw materials. This research aim to study the initial concentration and adsorption isotherm of Cr(VI) by using Mg/Al hydrotalcite in 180 minutes contact time. The Optimum initial concentration of Cr(VI) was 675 mg/L with 55,57 mg/g adsorption capacity. Isotherm adsorption was studied using Langmuir and Freundlich model. Based on the result, the adsorption of Cr(VI) fitted well with Langmuir isotherm model by 0,997 coefficient of determination
Utilization of Coal Bottom Ash a Low-Cost Adsorbent for the Removal Acid Red 114 Dye Kuntari Kuntari; Nurul Hidayat Aprilita; Suherman Suherman
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 17, ISSUE 1, February 2017
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol17.iss1.art2

Abstract

A research about adsorption of acid red 114 using coal bottom ash has been conducted. This research was aimed to examine the ability of coal bottom ash in acid red 114 adsorption. Some adsorption parameters i.e. dosage adsorbent, contact time and pH medium were examined in the adsorption processes. The characterization of coal bottom ash was determined using X-Ray Diffraction. Acid red 114 concentration is measured by using UV-Visible spectrophotometer. The adsorption percentage of acid red 114 on the coal bottom ash is 91.2% at pH 1.5; contact time 80 min, acid red 114 concentration 10 mg/L for every 1.5 g bottom ash.
An Investigation of Insect Ovipositing Repellent Activity of Andrographis paniculata Ness, Acacia auriculiformis and Piper betle Linn Leaves Extracts to Batrocera carambolae Nurcahyo Iman Prakoso; Umul Azizah; Zahrah Nur Zakiyah; Mila Tria Nita; Arida Liyanita; Suputa Suputa
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 18, ISSUE 1, February 2018
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol18.iss1.art1

Abstract

Batrocera carambolae was one of the main pests in some types of fruits. This pest attack resulted in quantitative damage in the form of fall of young fruit and qualitatively in the form of fruit to rot and contains maggots. This research was conducted to determine selected extract from Andrographis Paniculata Ness, Piper betle Linn and Acacia auriculiformis leaves which have repellent activity for Batrocera carambolae. Nine extracts from the maceration process of the three leaves were evaluated by placing the extracts and flies together in the cage. The ethanol, ethyl acetate, and n-hexane extracts from Andrographis Paniculata Ness, Piper betle Linn and Acacia auriculiformis leaves were applied to the test pieces and fed into a cage containing 10 male and female flies. From observation, N-hexane extracts from Andrographis Paniculata Ness and Piper betle Linn leaves and ethyl acetate extracts from Acacia auriculiformis leaf  having good activity as repellent and potentially to be used as a insect ovipositing repellent of Batrocera carambolae.
Pengaruh Durasi Iskemia terhadap Ekspresi Protein P53 Otak Tikus Pasca Transient Bilateral Common Carotid Artery Occlusion (TBCCAO) Ety Sari Handayani; Kuswati Kuswati; Zainuri Sabta Nugaha; Nurul Hidayah; Nesti Herennadia; Gea Sonia Amanda; Salsabila Ajeng
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 19, ISSUE 2, August 2019
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol19.iss2.art3

Abstract

Tumor suppressor gene p53 is one of the specific parameters of the occurrence of brain neuron death in animal models of brain ischemia. Several studies show that the duration of reperfusion of tBCCAO has an effect on the expression of p53 protein. The duration of ischemia for 5 minutes followed by reperfusion of 1 hour, 4 hours, 8 hours, 24 hours, and 7 days increased the expression of p53 protein. 30-minute ischemia induction followed by 4-hour reperfusion showed increased p53 protein expression in rat serum. It is not yet known how the influence of tBCCAO ischemia duration on p53 expression in rat brain. This study used Wistar, male rats, aged 3-4 months, weighing 175-250 gr, and healthy. Group A was a group of tBCCAO rats with a duration of 5 minutes ischemia, 24-hour reperfusion duration (five). Group B was a group of tBCCAO mice with a duration of 10 minutes ischemia, 24-hour reperfusion (five). Group C is a group of sham operated mice (five). The expression of p53 protein is semi quantification of p53 expressed on pyramidal neuron of the frontal brain (Cortex Prefrontalis, striatum) and CA1 hippocampus, with IHC staining using anti-p53 antibodies. P53 expression will be seen in the cytoplasm of pyramidal neuron CA1 hippocampus. Cytoplasm of neurons will be brownish in color. The semi-quantification method of p53 expression uses the ALLRED score. Data analysis using one way ANOVA test. The analysis found differences in frontal brain p53 expression (cortex prefrontalis and striatum) (p = 0.00) and there were differences in p53 expression in pyramidal neuron CA1 hippocampal (p = 0.013). There was an effect of the duration of tBCCAO on expression of p53 protein in rat brain after 24-hour reperfusion. Keywords: tBCCAO’s duration, p53, rat’s brain

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